class Treetop::Compiler::ParsingExpression

def var_initialization
  left, right = [], []
  var_symbols.each do |symbol|
    if init_value(symbol)
      left << var(symbol)
      right << init_value(symbol)
    end
  end
  if left.empty?
    ""
  else
    left.join(', ') + ' = ' + right.join(', ')
  end
end